Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754140AbbEZNVV (ORCPT ); Tue, 26 May 2015 09:21:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47502 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753654AbbEZNVE (ORCPT ); Tue, 26 May 2015 09:21:04 -0400 Message-ID: <5564732E.4090607@redhat.com> Date: Tue, 26 May 2015 15:20:46 +0200 From: Jerome Marchand User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Mel Gorman , Jeff Layton CC: "'Linux-MM'" , "'linux-kernel'" Subject: swap: nfs: Sleeping function called from an rcu read section in nfs_swap_activate Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="VdG3QUKOJp06cBiNPlvko4kEgmCHD33qj" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9005 Lines: 178 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --VdG3QUKOJp06cBiNPlvko4kEgmCHD33qj Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Commit dad2b015 added an rcu read lock around the call to xs_swapper() in nfs_activate()/deactivate(), which can sleep, thus raising a bug at each swapon and swapoff over NFS. I'm not sure if this is related or not, but swapoff also triggers the WARN_ON(sk->sk_forward_alloc) in sk_clear_memalloc(). [ 243.668067] =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D [ 243.668665] [ INFO: suspicious RCU usage. ] [ 243.669293] 4.1.0-rc1-lock_stat-dbg-next-20150430+ #235 Not tainted [ 243.670301] ------------------------------- [ 243.670905] include/linux/rcupdate.h:570 Illegal context switch in RCU= read-side critical section! [ 243.672163]=20 other info that might help us debug this: [ 243.673025]=20 rcu_scheduler_active =3D 1, debug_locks =3D 0 [ 243.673565] 2 locks held by swapon/1176: [ 243.673893] #0: (&sb->s_type->i_mutex_key#17){+.+.+.}, at: [] SyS_swapon+0x2b0/0x1000 [ 243.674758] #1: (rcu_read_lock){......}, at: [] nf= s_swap_activate+0x5/0x180 [nfs] [ 243.675591]=20 stack backtrace: [ 243.675957] CPU: 0 PID: 1176 Comm: swapon Not tainted 4.1.0-rc1-lock_s= tat-dbg-next-20150430+ #235 [ 243.676687] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 243.677179] 0000000000000000 00000000ef88d841 ffff88003327bcd8 ffffff= ff818861f0 [ 243.677854] 0000000000000000 ffff880078e38000 ffff88003327bd08 ffffff= ff8110d237 [ 243.678514] 0000000000000000 ffffffff81c650e4 0000000000000268 ffff88= 0078e38000 [ 243.679171] Call Trace: [ 243.679383] [] dump_stack+0x4c/0x65 [ 243.679811] [] lockdep_rcu_suspicious+0xe7/0x120 [ 243.680348] [] ___might_sleep+0xaf/0x250 [ 243.680815] [] __might_sleep+0x4d/0x90 [ 243.681279] [] mutex_lock_nested+0x47/0x430 [ 243.681762] [] static_key_slow_inc+0x7c/0xc0 [ 243.682264] [] sk_set_memalloc+0x27/0x30 [ 243.682736] [] xs_swapper+0x54/0x60 [sunrpc] [ 243.683238] [] nfs_swap_activate+0x93/0x180 [nfs] [ 243.683760] [] ? nfs_swap_activate+0x5/0x180 [nfs] [ 243.684316] [] SyS_swapon+0xad4/0x1000 [ 243.684766] [] ? syscall_return+0x16/0x59 [ 243.685245] [] system_call_fastpath+0x12/0x76 [ 243.685743] BUG: sleeping function called from invalid context at kern= el/locking/mutex.c:616 [ 243.686439] in_atomic(): 1, irqs_disabled(): 0, pid: 1176, name: swapo= n [ 243.687053] INFO: lockdep is turned off. [ 243.687429] CPU: 0 PID: 1176 Comm: swapon Not tainted 4.1.0-rc1-lock_s= tat-dbg-next-20150430+ #235 [ 243.688313] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 243.688845] 0000000000000000 00000000ef88d841 ffff88003327bd08 ffffff= ff818861f0 [ 243.689570] 0000000000000000 ffff880078e38000 ffff88003327bd38 ffffff= ff810df29c [ 243.690353] ffff880000000001 ffffffff81c650e4 0000000000000268 000000= 0000000000 [ 243.691057] Call Trace: [ 243.691315] [] dump_stack+0x4c/0x65 [ 243.691785] [] ___might_sleep+0x18c/0x250 [ 243.692306] [] __might_sleep+0x4d/0x90 [ 243.692807] [] mutex_lock_nested+0x47/0x430 [ 243.693346] [] static_key_slow_inc+0x7c/0xc0 [ 243.693887] [] sk_set_memalloc+0x27/0x30 [ 243.694416] [] xs_swapper+0x54/0x60 [sunrpc] [ 243.694959] [] nfs_swap_activate+0x93/0x180 [nfs] [ 243.695535] [] ? nfs_swap_activate+0x5/0x180 [nfs] [ 243.696193] [] SyS_swapon+0xad4/0x1000 [ 243.696699] [] ? syscall_return+0x16/0x59 [ 243.697299] [] system_call_fastpath+0x12/0x76 [ 243.702101] Adding 524284k swap on /mnt/swapfile512. Priority:-2 exte= nts:1 across:524284k FS [ 325.151350] BUG: sleeping function called from invalid context at kern= el/locking/mutex.c:616 [ 325.152688] in_atomic(): 1, irqs_disabled(): 0, pid: 1199, name: swapo= ff [ 325.153737] INFO: lockdep is turned off. [ 325.154457] CPU: 1 PID: 1199 Comm: swapoff Not tainted 4.1.0-rc1-lock_= stat-dbg-next-20150430+ #235 [ 325.156204] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 325.157120] 0000000000000000 00000000a7682b83 ffff88007ac3fce8 ffffff= ff818861f0 [ 325.158361] 0000000000000000 ffff880032434c00 ffff88007ac3fd18 ffffff= ff810df29c [ 325.159592] 0000000000000000 ffffffff81c650e4 0000000000000268 000000= 0000000000 [ 325.160798] Call Trace: [ 325.161251] [] dump_stack+0x4c/0x65 [ 325.162071] [] ___might_sleep+0x18c/0x250 [ 325.163073] [] __might_sleep+0x4d/0x90 [ 325.163934] [] mutex_lock_nested+0x47/0x430 [ 325.164927] [] atomic_dec_and_mutex_lock+0x4f/0x70 [ 325.166020] [] __static_key_slow_dec+0x27/0xc0 [ 325.166942] [] static_key_slow_dec+0x26/0x50 [ 325.167955] [] sk_clear_memalloc+0x2f/0x80 [ 325.169075] [] xs_swapper+0x41/0x60 [sunrpc] [ 325.170241] [] nfs_swap_deactivate+0x87/0x170 [nfs]= [ 325.171276] [] ? nfs_swap_deactivate+0x5/0x170 [nfs= ] [ 325.172349] [] destroy_swap_extents+0x77/0x90 [ 325.173754] [] SyS_swapoff+0x215/0x600 [ 325.174726] [] ? trace_hardirqs_on_thunk+0x17/0x19 [ 325.175971] [] system_call_fastpath+0x12/0x76 [ 325.178052] ------------[ cut here ]------------ [ 325.178892] WARNING: CPU: 1 PID: 1199 at net/core/sock.c:364 sk_clear_= memalloc+0x51/0x80() [ 325.180363] Modules linked in: rpcsec_gss_krb5 nfsv4 dns_resolver nfs = fscache ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_nat= ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_co= nntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security= ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf= _defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_secur= ity iptable_raw iosf_mbi crct10dif_pclmul crc32_pclmul crc32c_intel ppdev= ghash_clmulni_intel joydev nfsd parport_pc pcspkr virtio_console serio_r= aw virtio_balloon parport pvpanic i2c_piix4 acpi_cpufreq auth_rpcgss nfs_= acl lockd grace sunrpc virtio_blk qxl virtio_net drm_kms_helper ttm drm v= irtio_pci virtio_ring virtio ata_generic pata_acpi floppy [ 325.192279] CPU: 1 PID: 1199 Comm: swapoff Not tainted 4.1.0-rc1-lock_= stat-dbg-next-20150430+ #235 [ 325.193605] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 325.194491] 0000000000000000 00000000a7682b83 ffff88007ac3fdf8 ffffff= ff818861f0 [ 325.195692] 0000000000000000 0000000000000000 ffff88007ac3fe38 ffffff= ff810af5ca [ 325.196891] ffff88007ac3fe78 ffff88007b068000 ffff88007b484a00 ffff88= 007b484aa8 [ 325.198119] Call Trace: [ 325.198555] [] dump_stack+0x4c/0x65 [ 325.199380] [] warn_slowpath_common+0x8a/0xc0 [ 325.200601] [] warn_slowpath_null+0x1a/0x20 [ 325.201536] [] sk_clear_memalloc+0x51/0x80 [ 325.202468] [] xs_swapper+0x41/0x60 [sunrpc] [ 325.203398] [] nfs_swap_deactivate+0x87/0x170 [nfs]= [ 325.204426] [] ? nfs_swap_deactivate+0x5/0x170 [nfs= ] [ 325.205456] [] destroy_swap_extents+0x77/0x90 [ 325.206406] [] SyS_swapoff+0x215/0x600 [ 325.207287] [] ? trace_hardirqs_on_thunk+0x17/0x19 [ 325.208300] [] system_call_fastpath+0x12/0x76 [ 325.209248] ---[ end trace 13f1014b56e5e711 ]--- --VdG3QUKOJp06cBiNPlvko4kEgmCHD33qj Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJVZHM0AAoJEHTzHJCtsuoCpAMH/jn60kilHSsAcFoyn4ietrfJ svTWpaK77QuxrBakBkEWuZN1dHuxTqzoJLoxJw2ImmxLIKWYMB2IH6+LN+G7IWjz ilHw+2mvFg2V+8ZEj9ELeZcpm3j/wngS0VlvSr+Lpk0RgCta3cjURN+1SS1hHG5O v2/y59LMrElqSQjQaFssklGcgh4tP1hCN4YV3Qxqnme8ll9tOn21O/J8Or0IoYYc WjfWR/u5swa6OboeLx8tXxSM+DEMuXSVbEFRN2NGLj1JhDuBAyMw2hsZi85Y05oq 4KddXIfnCGuG7Fo0AVHMDO/vjK0TNbBrQF9dM6lqlBj2GiSehdhRPp5ISCGXUes= =tdzU -----END PGP SIGNATURE----- --VdG3QUKOJp06cBiNPlvko4kEgmCHD33qj-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/